Scientists are doubtful that the latest disease-producing
strain of avian flu detected in Nigeria originated with wild migratory birds
that annually migrate there from Europe or Central Asia. They say the newly discovered strain most
likely stems from the illicit or unreported trade of domestic poultry across
borders, a process that can be monitored and regulated if governments and
health authorities work to implement stronger, protective safeguards. Dr. Kristine Smith is Assistant Director of
the Wildlife Conservation Society’s Global Health Programs. She says that the current Class Three wave of bird influenza means a loss
of trade and the precautionary destruction of thousands of domestic poultry.

“For
Nigeria in particular, it’s been quite serious as far as their economy goes and
the direct impact on their poultry industry.
H5N1 being a zoonotic disease, meaning infectious to humans, it
continues to pose a threat to humans’ health.
These high-path H5N1 strains, as far as Nigeria is concerned, we are
watching it quite closely in the poultry markets because it obviously is a food
security issue,” she said.

Smith
says the reason that scientists who are tracking the spread of the disease are
dispelling reports of wild bird migrations causing the current bout in Nigeria
is that it has been shown that this year’s migration season has not yet begun.

“What
we have suspected has caused most of the outbreaks has been through the
movement of domestic poultry – domestic chickens or domestic ducks. These animals are moved both legally and
illegally within a nation and internationally, and that is how this disease
spreads quite a bit. However, wild
birds have played a relatively small role in moving the disease from country to
country during their migration movements; however, a lot of those times, those
infections don’t result in larger infections of poultry and people. This particular strain that has just hit
Nigeria has hit well before the migratory movement of birds heading south from
Europe and Asia, and so therefore, it’s not likely at all that wild birds
played a role in this new outbreak,” she stated.

The
Wildlife Conservation Society, which is based at New York’s famed Bronx Zoo,
continues to make a serious effort to heighten awareness of the need to trace
how poultry enters our food supply system.
Calling illegal food trade across borders a multi-billion-dollar
industry “comparable to the international drug trade,” Smith says the threat
posed by shipping poultry to markets domestically and across borders today is
greater than ever before.

“It’s
huge, and it’s not limited to poultry and even influenza, but both legal and
illegal movement of domestic and wildlife animals and products is largely
unrecorded and unregulated and undefined.
And given the increased globalization of today’s world, where we have
much more contact with different
species of animals, wildlife, and livestock and humans, with the trade, we’re
seeing an increase in occurrence of these major infectious diseases,” she
notes.

Smith,
a field veterinarian, credits the capability of Nigerian authorities to curb
the spread of the influenza.

“Nigeria
has been one of those countries that have been wonderfully working very
diligently -- their government, with their internal forces and external
international assistance. And they’re
doing a wonderful job of responding to these outbreaks,” she says.

Smith
points to some advantages that Nigeria has that have enabled its medical and
civil authorities to contain the country’s multiple outbreaks effectively.

Sometimes,
even though a developing country may have a little bit less infrastructure,
sometimes it’s easier for them to contain some of these outbreaks because you
don’t have the highways, you don’t have so many commercial poultry farms, where
you have people moving from one to another constantly. And so in some ways, it’s almost easier to
keep a handle on some of these outbreaks in developing countries as opposed to
more developed countries. But it always
varies on the type of outbreak that occurs, where it occurs, and in what
species it occurs,” she notes.

Although vaccines to lessen the
severity of the illness continue to be developed, Smith notes that the virus is
constantly adapting and unfolding in new strains. While, the impact of bird flu has thankfully not reached the
dreaded levels that were feared two and three years ago, more work remains to be
done to find a definitive explanation of how the avian influenza makes its way
to countries like Nigeria or to countries like Egypt and Indonesia, where it
has taken an even greater economic and human toll.